Carton partition forming and article handling machine

ABSTRACT

Pregrouped slugs of articles are fed onto a deadplate table, where each slug is successively advanced by a primary flight bar through several machine stations. The columns of articles in each slug are spread laterally by lane dividers, and unique column partition elements, or separators, are fed from fixed magazines at several successive machine stations between the columns as they are so spread. The primary flight bars are driven through a lost motion mechanism to slow the slug at these machine stations, and the adjacent rows of articles in each slug are tilted at other machine stations to allow row separators to be fed between the adjacent rows, and to mate with the column separators to form a partition which is held in place by the articles themselves. A secondary flight bar provided ahead of each of the slug of articles serves to restrain the front row of articles in each slug as the slug is decelerated and accelerated at the various machine stations. This secondary flight bar is carried by the flight bar chains on cam operated devices which permit the secondary flight bar to be moved ahead during the lost motion referred to above.

United States Patent [1 1 McIntyre CARTON PARTITION FORMING AND ARTICLE HANDLING MACHINE [75] Inventor: Daniel McIntyre, Portland, Conn.

[73] Assignee: Emhart Corporation, Bloomfield,

Conn.

[22] Filed: Oct. 13, 1971 [21] Appl. No.: 188,820

[52] US. Cl 53/159, 53/157, 198/34 [51] Int. Cl B65b 35/44, B65b 61/00 [58] Field of Search 53/26, 35, 157, 159;

[56] References Cited UNITED STATES PATENTS 2,968,898 l/196l Hickin 53/26 2,930,174 3/1960 Moreno 53/50 X 3,481,108 12/1969 Englander et a1... 53/160 3,350,836 11/1967 Dillon et a1 53/157 X 2,615,289 10/1952 Hickin t 53/157 X 3,651,614 3/1972 Corderoy 53/35 X Primary Examiner-Robert L. Spruill Att0rney.1ohn C. Hilton STATION STATION STATION A B C 5 7 ABSTRACT Pregrouped slugs of articles are fed onto a deadplate table, where each slug is successively advanced by a primary flight bar through several machine stations. The columns of articles in each slug are spread laterally by lane dividers, and unique column partition elements, or separators, are fed from fixed magazines at several successive machine stations between the columns as they are so spread. The primary flight bars are driven through a lost motion mechanism to slow the slug at these machine stations, and the adjacent rows of articles in each slug are tilted at other machine stations to allow row separators to be fed between the adjacent rows, and to mate with the column separators to form a partition which is held in place by the articles themselves. A secondary flight bar provided ahead of each of the slug of articles serves to restrain the front row of articles in each slug as the slug is decelerated and accelerated at the various machine stations. This secondary flight bar is carried by the flight bar chains on cam operated devices which permit the secondary flight bar to be moved ahead during the lost motion referred to above.

7 Claims, 8 Drawing Figures STATION STATION STATION D E F PATENIEDSEPZSIHH sum 3 OF 4 m wE CARTON PARTITION FORMING AND ARTICLE HANDLING MACHINE BACKGROUND OF THE INVENTION Prior art partition assemblies, for use in a carton in the packing of glassware or the like, are usually selfsupporting and are inserted in the carton prior to dropping, or otherwise inserting the glassware articles in said carton. These partition assemblies are generally collapsible but must nevertheless be self-supporting to be used in this manner.

A more advanced concept of assembling a partition between the bottles or jars, so that the articles themselves serve to support the partition elements, is suggested in a patent application entitled Carton Partition Assembly" filed Apr. 19, 1971 under Ser. No. 135,272 and assigned to the assignee herein. This unique partition assembly permits a substantial saving in paperboard weight and therefore in the cost of the partition as a result of its unique construction. The machine to be described herein is intended for use in handling the partition separators shown and described in this patent application and permits'the use of a typical wrap around cartoning machine of the typeshown in U.S. Pat. No. 3,513,630 issued May 26, 1970 and assigned to the assignee herein.

Thus, the primary object of the present invention is to provide an improved machine for use in conjunction with partition elements of the type shown and described in the carton partition assembly patent application referred to above to provide a slug of articles together with an associated partition both of which comprise a unit readily adapted for cartoning in a carton partition machine of the type referred to above, or for use in a tray forming machine or other high speed packaging machine.

SUMMARY OF THE INVENTION This invention relates generally to machines for forming carton partitions, and deals more particularly with an apparatus for handling slug of articles to be packaged, and for forming the partition in spaces provided between the rows and columns of articles in the slug as the latter is conveyed through various stations of the machine.

In accordance with .the present invention segregated slugs of articles are fed through the machine by primary flight bars conventionally mounted on chains and entrained over sprockets at either end ofthe machine. The columns of articles in the slugs are spread laterally by lane dividers to provide spaces at several initial stations in the machine, and partitions or separators are fed from fixed magazines above the path of movement of the slugs as the primaryflight bars are slowed to a near standstill on the. underlying deadplate table at the stations. The slugsarethen, accelerated slightly after the partitions have been so fed, and at the downstream stations a similar deceleration and acceleration occurs in conjunction with -a ramp on the deadplate table for tilting the adjacent rows of articles in each of the slugs so that row partitionelements, arrangedperpendicular to the column partitions, can ,be fed ontthe column partitions to provide apackage as described onto the above mentionedpatentapplication, entitled Carton Partition Assembly :-filed-Apr. 19, 1971 under Ser. No. 135,272. A secondaryvflight bar is preferably provided during highspeed operation of the machine for restraining the forward end of each of the slugs of articles as each slug is decelerated and accelerated at each machine station. This secondary flight bar is itself advanced and retarded with respect to the slug of articles at certain of these stations in order to permit the above mentioned tilting of the adjacent rows of articles for accepting a row partition between the adjacent rows in each slug.

The following disclosure is directed to the packaging of some 12 glass bottles with three separators for the four columns in each slug, and wit two separators for the three rows or articles in each slug. It will be of course apparent that a machine can be built to accommodate any number of rows and columns of articles in a slug within the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of an upstream portion of a machine incorporating the present invention, showing the three upstream machine stations A, B and C.

FIG. 2 is a side elevational view ofa downstream portion of the machine shown in FIG. 1 showing three downstream stations D, E and F.

FIG. 3 is a horizontal sectional view [taken on the line 33 of FIGS. 1 and 2] showing the formation of the articles in each of the slugs at the various machine stations.

FIG. 4 is a perspective view showing three of the 12 articles in a single slug, with the paperboard separators in place therebetween as they would appear at the downstream station F of FIG. 3.

FIG. 5 is a side elevational view of two of the three stations shown in FIG. 2, that is stations D and E.

FIG. 6 is a sectional view taken along the line 6-6 of FIG. 1 showing one of the magazines associated with one of the machine stations of FIG. 1.

FIGS. 7 and 8 show the two positions of the forward flight bar at stations C and D being taken on line 7-7 and-88 of FIG. 3 respectively.

DETAILED DESCRIPTION Pregrouped slugs of articles are adapted to be fed into the upstream end of the machine shown in FIG. 1 in the direction of the arrow 10 by an infeed conveyor 12 of conventional configuration. A load grouper or other suitable device (not shown) segregates columns of articles into the desired array size, with a predetermined number of rows and columns as required for a wrap around carton forming machine or the like provided for this purpose at the downstream end of the machine to be described.

FIGS. 1 and 2 taken together show the overall machine ascomprising a fixed frame, with end supports 14 and 16 for rotatably carrying sprockets l8 and 20 respectively. The downstream sprocket 20 is adapted to being driven in the direction shown at 22, through a lost motion device, indicated generally at 24 and to be described in greater detail hereinafter, through a motor 26. Flight bar chains 28, 28 (only one of which is shown) are entrained over the sprockets 18 and 20 so that the lower run of the chain is adapted to move from left to right as viewed in FIGS. 1 and 2. Primary flight bars 30, 30 are provided at spaced intervals on these flight bars chains for advancing the slugs of articles in the downstream direction, indicated, through the various machine stations A-F to be described.

A flat table, or deadplate 32, provides a fixed surface across which the slugs of articles can be moved by the primary flight bars 30, 30 as best shown in FIG. 3 lane defining means is also provided for guiding the columns of articles in the various slugs as they are advanced from left to right through the machine by these flight bars 30, 30.

The lane defining means includes fixed outer guides 34 and 36 which are spaced from one another, in the upstream portion of the machine, a predetermined distance, somewhat greater than the diameter of the individual articles times the number of columns in a slug. In the downstream portion of the machine, on the other hand, these outside lane guides 34 and 36 are spaced a distance apart dictated by the number of columns of articles in a slug. As shown at the left hand side of FIG. 3 a central lane divider 38 is provided midway between the outside lane guides 34 and 36, and the thickness of the divider 38 is such that the articles in the two center columns are spread apart laterally at station A to provide a space into which a separator or partition element 40acan be dropped by the apparatus shown in FIG. 6.

Still with reference to FIG. 3, it can be seen that at station B another separator 40b is inserted between still another adjacent two columns in the slug by the guide 70. This guide 70 spreads the outside column of articles with respect to one of the central columns in order to provide a space for receiving the partition separator 40b. Station C shows a similar lane defining configuration 72 for spreading the right hand column with respect to the other central column in the slug for receiving still another separator 40c. The three separators, inserted in the slugs at the successsive stations A, B and C, are shown in FIG. 4 at 40a, 40b and 40c respectively. Only three of the articles are shown in this view to better unique partition assembly.

As shown in FIG. 6, the separator 40a is shown at the instant when it is inserted in the space provided between these spaced central columns of articles at station A. This separator 40a is fed from a magazine of similar cardboard separators supported on rails l7, 17 provided for this prupose in the fixed frame of the machine.

Turning now to a more detailed description of the magazine shown in FIG. 6, upright angles supports 42, 42 are mounted to a fixed support 44, which support 44 is in turn carried by the laterally extending guides 17, 17. A stack of separators 40a is provided between these angle members 42, 42 and a front wall 46 on the magazine is removable mounted on support posts 48, 48 provided for this purpose. A weight 50 at the upper end of the stack 40a may be utilized to exert the desired downward pressure on the separators in the magazine. The lowermost separator in the magazine is adapted to be sequentially withdrawn by a stripper plate 52 one end of which is adapted to be engaged by a movable member 54 carried on the end of a piston rod 56. The movable member 54 includes an abutment 58, which abutment is adapted to engage the free end of a spring loaded plunger 60, and the plunger 60 carries at its opposite end a shelf or door 62, which door is adapted to support a blank 40a in the hopper 64 and to release said separator 40a from said hopper 64, in timed relationship with movement of a slug of articles through station A. A fluid motor 66 is provided immediately below the magazine for sequentially reciprocating the piston rod 56 in order to release a separator 40a from the hopper as described, and in order to move the stripper plate horizontally to the left as viewed in FIG. 6 so as to strip a separator 40a from the stack in the magazine each time that a separator is so released. Still with reference to FIG. 6, the lane defining means 38 providing the space between the central columns of the slug of articles for receiving the separators 400 has a canted upper surface, indicated generally at 68, which prevents the separator 40a from bouncing out of position after being dropped by gravity from the hopper.

Similar magazines are provided at stations B and C for feeding the separators 40b and 400 between associated adjacent columns of articles in the slug. These magazines are similar in construction to that shown and described with reference to FIG. 6, and with reference to station A, and need not be described in detail herein. It should however be noted that the canted surface 68 associated with the central lane guide 38 is also utilized in association with lane guides 70 and 72 for separating the associated columns of articles at stations B and C respectively. It should also be noted that the lost motion mechanism, mentioned hereinabove with reference to FIG. 2, and indicated generally by the reference numeral 24, is adapted to slow the slugs of articles in their progress through stations A, B and C in order to provide a sufficient time interval for receiving the separators 40a, 40b and 40c respectively. However, a description of this lost motion mechanism will be postponed until stations D and E are described in detail since it is at these latter stations where the row separators 72a and 72b are united with the slug of articles that the lost motion mechanism is of special usefulness.

A secondary flight bar 74 is provided in spaced upstream relationship to each of the primary flight bars 30 for restraining the slugs of articles as they are accelerated and decelerated through each of the successive stations, A through F inclusively, in the machine. This secondary flight bar 74 is mounted at either end to associated bellcranks 76, 76 and each bellcrank carries a pivot pin 78, which pivot pin is in turn carried by the same flight bar conveyor chain associated with the primary flight bars 30, 30. Thus, as the slug of articles are conveyed through stations A, B and C the forward flight bar 74 associated with each primary flight bar 30 is so positioned as to restrain the slug in the configuration shown to best advantage in FIG. 3. However, as the slugs of articles are advanced through stations D and E this forward flight bar will be moved forward slightly as a result of the relative angular movement of the bellcranks 76, 76 as best shown in FIGS. 7 and 8. Finally, and still with reference to the bellcranks 76, 76 each such bellcrank carries a cam follower 80 at its upper corner, which cam follower 80 is adapted to engage a fixed cam 82 and to thereby rotate these bellcranks 76, 76 as the secondary, or forward flight bar 74, passes around the driven sprocket 20 associated with the downstream end of the machine. This cam action assures that the secondary or forward flight bar 74 clears the top of the articles in the forward row of that particular slug as that slug is discharged by the associated primary flight bar 30 onto a take away conveyor, or into a cartoning machine. At stations D and E the row separators 72a and 72b, used to isolate adjacent rows of articles in each slug, are inserted in spaces provided therefore as a result of tilting the adjacent rows of articles relative to one another even as the primary flight bars 30, 30 move these slugs through the machine.

Ramp surfaces 90 and 92 at stations D and E respectively, serve to tilt the articles in the adjacent rows, oppositely to one another in order to provide a V-shaped opening for receiving the row separators 72a and 72b from associated hoppers, 64d and 64:: respectively. Each of these hoppers 64d and 64e is associated with a magazine, 42d and 422 respectively, and these magazines are generally similar in construction to that described hereinabove with reference to FIG. 6, except that a single air cylinder 66a is utilized for operating both of the stripper plates associated with these individual magazines and also for operating the associated doors at the bottom of the respective hoppers 64d and 64e respectively. The configuration of this dual, or tandum magazine construction is shown to best advantage in FIG. 5.

With particular reference to FIGS. 7 and 8, the for- ,ward or secondary flight bar 74 can be seento be adapted for downward movement at the stations D and E of FIG. 2 causing the above described angular rotation of the bellcranks 76, 76 which support this forward flight bar. This downward motion of the bar 74 moves said bar forwardly with respect to the primary flight bar so as to facilitate the tilting motion of the article rows described above. A fixed cam surface is provided for this purpose in the side guides 34 and 36 with the notches, indicated generally at 85d being so located that the bars 74, 74 move forwardly and downwardly at the proper point in time during each machine cycle. One of these notches 85d is shown in FIGS. 7 and 8 buts its function is typical of the notch (not shown) associated with the other side guide, or lane guides 36.

By way of summary, the partition elements or column separators 40a, 40b and 400 are inserted between adjacent columns of articles in the slugs, as the slugs are carried through stations A, B and C respectively, and the somewhat deeper row separators 72a and 72b are thereafter inserted into the V-shaped notches defined in the upper edges of the column separators at stations D and E respectively. The reader is referred to the above mentioned patent application entitled carton partition assembly filed Apr. 19, 1971 under US. Pat. No. 135,272 for a more complete description of the geometry of the separators. For present purposes it is sufficient to note that these separators are so designed as to be conveniently stored in magazines, and to provide adequate protection between adjacent articles in an array or slug for packaging in a wrap around carton type packaging machine. While other type partition elements might be used in the present machine those described in the above mentioned patent application provide individual partition elements which can be cut from a continuous strip of relatively thin paperboard material with a minimum of waste as a result of their unique geometry.

Station F comprises a push down" station wherein a plunger 88 is adapted to be periodically lowered so as to assure that the row separators 72a and 72b are seated in the position shown in FIG. 4, that the column separators 40a and 40b and 400 are also in place. As the slugs of articles exit from the downstream end of the machine shown in FIG. 2, the forward or secondary flight bar 74 is adapted to be canted by the cam, through the action of the cam follower 80. The primary flight bar 30 slides the slug of articles, with its associated partition elements in place as shown in FIG. 4,

onto a take-away conveyor or into a cartoning machine.

The above described machine is continuously operated, but not at a constant speed, and a lost motion mechanism, indicated generally at 24 in FIG. 2, is utilized to decelerate the slugs of articles as they enter in each of the successive stations described above, and to thereafter accelerate the slugs back to a normal speed as the slugs are transferred from one station to a succeeding station in the machine. This lost motion mechanism has an input drive shaft which is continuously rotated at a constant angular velocity by the motor 26. The input drive shaft 100 carries a cam 102, which cam engages a cam follower 104 provided for this purpose on a pivoted lever 106. The lever 106 comprises one element of a three bar linkage, the other two elements comprising a similar lever 108 together with the cross member 110. Thus, the levers 106, 108, and 110 comprise a movable frame which is adapted to oscillate sprockets and 122 between limit positions dictated by the geometry of the cam 102. This linkage frame 106, 108 and 110 is pivoted at the lower end of the machine frame. The input drive shaft 100 of the lost motion mechanism also carries a drive sprocket 112 which is also driven with constant angular velocity and around which is entrained a drive chain 114. This drive chain 114 is entrained over additional idler sprockets 116 and 118, as well as two sprockets 120 and 122 provided on the movable frame referred to above. Finally, and still with reference to the drive chain 114, a driven sprocket 124 is adapted to be rotated in the direction indicated at 126 by the drive chain 114. An output or driven shaft 128 for the sprocket 126 also carries a second sprocket 130 around which is entrained a drive chain 132, which drive chain is adapted to rotate the sprocket 20, associated with flight bar chain 28 in the direction indicated at 22, for operation of the flight bars 30 and 74. The configuration of the flexible drive element 114 fo the lost motion device is such that .it has two strands which are adapted for movement in either the normal direction of motion of said flight bar chain 28, or against said direction of motion so as to achieve two-for-one reduction in speed of the output of the drive shaft 128 as the cam 102 rotates. Thus, the cam follower 104 is urged toward and away from the input drive shaft 100 by the drive element 114 and the cam 102 whereby respectively, to swing the movable frame 106, 108 and 110 and sprockets 120, 122 is counterclockwise and clockwise directions and thereby to decelerate and accelerate the shaft 128. The cam follower 104 is held in engagement with the cam 102 by virtue of the rotation of the drive sprockets on shaft 100 pulling the drive chain against the resistance of the driven sprocket 124. It will be apparent that depending upon the contour of the cam 102 and upon the input speed of thedrive shaft 100 a variation in speed of the flight bar conveyor can be achieved, and that the speed of the slugs of articles as they pass through the various stations in the machine can actually be reduced to zero relative to the fixed deadplate table 32. This stopping of the articles may not be necessary, however, and as long as the row partitions 72a and 72b can be dropped into the V-shaped openings, caused by the vamps 90 and 92 at stations D and E respectively, at some speed slower than that of the normal operating speed of the flight bars the advantages of the present invention can be realized.

What is claimed is:

l. A machine for handling articles to be packaged and comprising: flight bar conveyor means including a flat deadplate table for receiving pre-grouped slugs of articles and including primary flight bars for advancing these slugs through several successive machine stations, drive means for said flight bar conveyor and including a lost motion mechanism for sequentially slowing the speed of movement of the flight bars as the slugs pass through said machine stations and thereafter accelerating said slugs to normal speed, lane defining means for positively limiting the articles to movement in a plurality of side-by-side columns, said lane defining means including means for laterally spacing two adjacent columns at one of said machine stations, and first means for inserting a separator between said spaced columns of articles and during said lost motion slowing of said flight bar conveyor so that the separator is thereafter moved along by the flight bar associated with that particular slug, second means for inserting a second separator between another two adjacent columns at a second machine station, said lane defining means also including means for spacing said another two adjacentcolumns of articles in said slugs at said second machine station, and each of said first and second separator inserting means comprising a magazine for storing separators in stacks and associated separator stripping means, said last-mentioned means comprising a stripper plate of compatible thickness for said separator, means for cyclically moving said plate across the lower end of the magazine to feed the lowermost separator from the stack in its own plane, a hopper for receiving the separator so stripped and supporting it on edge, and a door at the bottom of the hopper, said stripper plate moving means also serving to open the door during each cycle to release the blank in the hopper for free fall into the space provided in the slug of articles at that station.

2. The machine set forth in claim 1 further characterized by ramp means on said deadplate table at another one of said machine stations for tilting two adjacent rows of articles in each slug in opposite directions to provide a space therebetween as the slug is slowed during movement through said another one of said machine stations, and means for inserting a separator between said spaced rows of articles and during said lost motion slowing of said flight bar conveyor.

3. The machine set forth in claim 1 further characterized by said flight bar conveyor means further including secondary flight bars, each of which secondary flight bars is normally spaced upstream of one of said primary flight bars for guiding the slugs of articles therebetween as it is advanced through said successive machine stations.

4. The machine set forth in claim 3 further characterized by said flight bar conveyor means comprising a single pair of flight bar supporting chains for said primary flight bars, and means connecting said secondary flight bars to said flight bar supporting chains so that they are normally spaced upstream of said primary flight bars and are movable upstream with respect to said chains during said lost motion slowing of said primary flight bars at said still another machine station to allow said tilting of said two adjacent rows for insertion of said separator into said V-shaped space as aforesaid.

5. The machine set forth in claim 4 further characterized by said means connecting said secondary flight bars to said flight bars supporting chains comprising a pair of bellcranks pivotally connected to said chains and supporting each of said secondary flight bars in spaced relation to the axis of each pivotal flight bar connection, a cam follower carried by each bellcrank also mounted in spaced relation to said axis, and fixed cams provided adjacent the paths of movement of said flight bar chains for normally restraining said bellcranks to hold said secondary flight bars in their normal positions with respect to said primary flight bars respectively and for pivoting said bellcranks at said still another machine station to increase said normal spacing to allow said tilting by said ramp means.

6. The machine set forth in claim 1 further characterized by said lost motion mechanism comprising an input drive shaft adapted for continuously constant angular rotation in one direction, a cam carried by said drive shaft, a movable frame having a cam follower for engaging said cam, a flexible driving element entrained on sprockets located on said drive shaft and on said movable frame, an output shaft with a sprocket for said flexible driving element, and means for tensioning said driving element so that said frame is oscillated between limit positions defined by said cam.

7. The machine set forth in claim 6 further characterized by said lost motion mechanism further comprising at least two sprockets on said movable frame, and at least four relatively fixed sprockets including said input drive and said output driven sprockets, said flexible element being entrained around all six of said sprockets to provide two strands between said movable sprockets and said fixed sprockets, said cam being so shaped that said frame is moved at one half the speed of linear movement of said chain at said input drive sprocket whereby said output drive sprocket is momentarily stopped when said flight bars are at said machine stations as aforesaid. 

1. A machine for handling articles to be packaged and comprising: flight bar conveyor means including a flat deadplate table for receiving pre-grouped slugs of articles and including primary flight bars for advancing these slugs through several successive machine stations, drive means for said flight bar conveyor and including a lost motion mechanism for sequentially slowing the speed of movement of the flight bars as the slugs pass through said machine stations and thereafter accelerating said slugs to normal speed, lane defining means for positively limiting the articles to movement in a plurality of side-by-side columns, said lane defining means including means for laterally spacing two adjacent columns at one of said machine stations, and first means for inserting a separator between said spaced columns of articles and during said lost motion slowing of said flight bar conveyor so that the separator is thereafter moved along by the flight bar associated with that particular slug, second means for inserting a second separator between another two adjacent columns at a second machine station, said lane defining means also including means for spacing said another two adjacent columns of articles in said slugs at said second machine station, and each of said first and second separator inserting means comprising a magazine for storing separators in stacks and associated separator stripping means, said last-mentioned means comprising a stripper plate of compatible thickness for said separator, means for cyclically moving said plate across the lower end of the magazine to feed the lowermost separator from the stack in its own plane, a hopper for receiving the separator so stripped and supporting it on edge, and a door at the bottom of the hopper, said stripper plate moving means also serving to open the door during each cycle to release the blank in the hopper for free fall into the space provided in the slug of articles at that station.
 2. The machine set forth in claim 1 further characterized by ramp means on said deadplate table at another one of said machine stations for tilting two adjacent rows of articles in each slug in opposite directions to provide a space therebetween as the slug is slowed during movement through said another one of said machine stations, and means for inserting a separator between said spaced rows of articles and during said lost motion slowing of said flight bar conveyor.
 3. The machine set forth in claim 1 further characterized by said flight bar conveyor means further including secondary flight bars, each of which secondary flight bars is normally spaced upstream of one of said primary flight bars for guiding the slugs of articles therebetween as it is advanced through said successive machine stations.
 4. The machine set forth in claim 3 further characterized by said flight bar conveyor means comprising a single pair of flight bar supporting chains for said primary flight bars, and means connecting said secondary flight bars to said flight bar supporting chains so that they are normally spaced upstream of said primary flight bars and are movable upstream with respect to said chains during said lost motion slowing of said primary flight bars at said still another machine station to allow said tilting of said two adjacent rows for insertion of said separator into said V-shaped space as aforesaid.
 5. The machine set forth in claim 4 further characterized by said means connecting said secondary flight bars to said flight bars supporting chains comprising a pair of bellcranks pivotally connected to said chains and supporting each of said secondary flight bars in spaced relation to the axis of each pivotal flight bar connection, a cam follower carried by each bellcrank also mounted in spaced relation to said axis, and fixed cams provided adjacent the paths of movement of said flight bar chains for normally restraining said bellcranks to hold said secondary flight bars in their normal positions with respect to said primary flight bars respectively and for pivoting said bellcranks at said still another machine station to increase said normal spacing to allow said tilting by said ramp means.
 6. The machine set forth in claim 1 further characterized by said lost motion mechanism comprising an input drive shaft adapted for continuously constant angular rotation in one direction, a cam carried by said drive shaft, a movable frame having a cam follower for engaging said cam, a flexible driving element entrained on sprockets located on said drive shaft and on said movable frame, an output shaft with a sprocket for said flexible driving element, and means for tensioning said driving element so that said frame is oscillated between limit positions defined by said cam.
 7. The machine set forth in claim 6 further characterized by said lost motion mechanism further comprising at least two sprockets on said movable frame, and at least four relatively fixed sprockets including said input drive and said output driven sprockets, said Flexible element being entrained around all six of said sprockets to provide two strands between said movable sprockets and said fixed sprockets, said cam being so shaped that said frame is moved at one half the speed of linear movement of said chain at said input drive sprocket whereby said output drive sprocket is momentarily stopped when said flight bars are at said machine stations as aforesaid. 